Authors

Source

Abstract

Most of the theoretical studies published to-date on the structural and electronic properties of supramolecules have been devoted to the neutral or cationic co mplexes, while little is known about anionic systems. A detailed theoretical study of the interaction between simple aromatic amides and the bromide anion has recently been published (Cajan, M.; Stibor, I.; Koca, J. J. Phys. Chem. A 1999, 103, 3778). The present work focuses on the structural and physico-chemical parameters of simple aromatic amides related to their ability to form the 1:1 complex with a bromide anion. A quantitat ive structure-property relationships (QSPR) model for the prediction of association constants is proposed. The model based on 22 complexes and 9 molecular descriptors explained 96% (84% cross-validated) of the variance in association constants. The descriptors employed in this model included parameters for the characterization of conformational behavior and the 3D structure of amide molecules, distribution of electron density on the amidic functional group and parameters for substitution on aromatic units. The quantitative structure-property relationship approach predicted the association constants with comparable quality, but significantly lower computational demand, than molecular modeling or standard quantum chemistry calculations.